THE OVERALL GOAL OF THE PROJECT IS TO INTEGRATE A SET OF STATE OF THE ART TECHNOLOGY DESIGNED TO ALLOW THE IDENTIFICATION OF ALL GENES INVOLVED IN SPECIFIC PHYSIOLOGICAL PROCESSES WITHOUT THE NEED FOR DRAMATIC MUTANT PHENOTYPES. INHERENT LIMITATIONS TO COMPREHENSIVENESS IN MUTANT HUNTS AND PHENOTYPE ANALYSIS - REDUNDANT FUNCTIONS, PLEIOTROPIC FUNCTIONS, ESSENTIAL FUNCTIONS, AND FUNCTIONS THAT ACT DOWNSTREAM OF MAJOR REGULATORY ACTIVITIES, SUCH AS PROTEIN KINASE SUBSTRATES OR SUBSTRATES OF DEGRADATION PATHWAYS -- WARRANT NOVEL APPROACHES. THESE APPROACHES ENABLED BY THE CONCURRENT MATURATION OF SEVERAL NEW TECHNOLOGIES - THE MOST IMPORTANT BEING COMPLETION OF THE SEQUENCING OF THE SACCHAROMYCES CEREVISIAE GENOME AND DRAMATIC IMPROVEMENTS IN ANALYSIS OF PROTEINS BY 2D GELS AND MASS SPECTROMETRY.